The paper tentatively explores factors leading to Hawthorne's creation of The Scarlet Letter by careful examination of the preface "Custom House", and finds that Hawthorne's experience at the Salem Custom House inspired the fantasy of The Scarlet Letter, while his ouster eventually triggered the creation of the fiction. Nathaniel Hawthorne, the great literary genius in American literature during the Age of Romanticism, was by nature serious and reclusive;therefore, his works are often dark, gloomy. Living in an age witnessing great changes, Hawthorne was willing to accept a new set of values and belief quite different from those held by his puritan ancestors.